Final answer:
The statement is True - a planet-satellite system must be isolated from other massive objects to follow Kepler's laws of planetary motion. Therefore, the given statement is True.
Step-by-step explanation:
The statement is True - a planet-satellite system must be isolated from other massive objects to follow Kepler's laws of planetary motion. Kepler's laws were derived based on observations of the motions of planets and their satellites in our solar system, which can be considered as an isolated system with negligible influence from other massive objects. If the system is influenced by other massive objects, such as nearby planets or moons, the motion of the planet-satellite system may not precisely follow Kepler's laws.